Gaseous electric discharge device



March 13, 1934. G. GREEFF GASEOUS ELECTRIC DISCHARGE DEVICE Filed Jan. 13, 1931 INVENTOR ATTORNEY Patented Mar. 13, 1934 1,951,294 GASEOUS ELECTRIC DISCHARGE DEVICE Gerhard Greefl, Berlin,

' General Electric Company,

New York Germany, assignor to a corporation of Application January 13, 1931, Serial No. 508,499 In Germany March 5, 193i) 3 Claims. (Cl. 176-124) 6 are sealed into said device 7 at the ends thereof.

The present invention relates generally to gaseous electric discharge devices and particularly the invention relates to starting and operating means for such devices.

It is well known in the art that gaseous electric discharge devices having electrodes which are electron-emitting when heated may be started into operation by the application of a high volt age surge, or by the application of a high frequency current to such devices. It has heretofore been the practice in the art in the use of high frequency current for such purpose to employ a time delay switch mechanism, such as a thermostatic device, to cut out of circuit the high frequency apparatus during the operation of the electric discharge device as the active time of the high frequency apparatus is extremely short in comparison to the operating time of the electric discharge device. As the time required for starting electric discharge devices into operation varies considerably such time delay switch mechanisms are unsatisfactory in that the high frequency apparatus is often left in the circuit for an appreciable time after the electric discharge device has been started into operation when, as will be apparent, it is no longer needed.

The object of the present invention is to provide a simple and positive acting means to cut out of circuit the high frequency apparatus instantly on the initiation of the operating discharge in electric discharge devices.

In accordance with this object the invention comprises a relay connected into one of the electrode leads of said electric discharge device and a. switch connected into a lead of the high, frequency apparatus, said relay being adapted to operate said switch to cutout of circuit the high frequency apparatus instantly on the start of the operating discharge in said electric discharge device. The heating circuit for the electron emitting electrodes is broken in the same operation, when desired, by bridging the leads of the high frequency apparatus across the leads of the primary winding of the heating circuit transformer, the secondary windings of said transformer being connected to heat the respective electrodes of said device.

In the drawing accompanying and forming part of this specification an embodiment ofthe invention is shown schematically for purposes of disclosure.

Referring to the drawing the electric discharge device '1 is filled with a discharge conducting atmosphere such as a gas, or a vapor, or mixtures of these, and electron-emitting electrodes 5 and Said electrodes 5 and 6 are connected to terminals 1 and 2 of a current supply source by leads 3 and 4 respectively.

Switch 8 and choke coil 9 or a ballast resistance are connected into lead 3 as is the well known-practice in the art. Electrode leads 3 and 4 are bridged by leads 10 of the high frequency apparatus 11 through switch 24, said high frequency apparatus consisting of a spark gap, an inductance, an oscillatory circuit and a high frequency transformer in the case of an alternating current source and consisting of a magnetically operated circuit breaker and an inductance rent source as is wel in the case of a direct cur- 1 known in the art. The

leads 12 from said high frequency apparatus 11 are connected to the electric discharge device '7 in any suitable manner as by connecting one of them to each of the wrapping them in the the container of said electrodes 5 and 6 or by form of a loop 13 around device '7 in the vicinity of the electrodes 5 and 6 as illustrated in the and 6 directly by leads 19 10 are bridged by the pritransformer 15, 16, 17 be by leads 14, the secondary 17 being connected to electrodes 5 and 21 respectively and indirectly byleads 18 and 20 connecting with electrode leads 3 and 4 to supply heating current to said electrodes 5 an lay 22, 23 is connected into The winding 22 of reelectrode lead 3, the

core 23 of said relay 22, 23 being adapted to operate switch lever 24 leads 10 of the high connected into one of the frequency apparatus.

To start electric discharge device '7 into operation switch 8 is closed and current then flows to electrodes 5 and 6 through the heating circuit emitting temperature apparatus 11. When heated to an electron and have emitted sufiicient electrons, which requires in the order of thirty seconds or less, lished in said device 7 as is now well understood.

On the establishing of the operating discharge, winding 22 of the relay 22, 23 is energized and core 23 attracts switch cuit the high frequency transformer 15, 16, 1'7 the discharge should 0 apparatus 11 and the of the heating circuit. If

easefor any reason caused,-

switch lever 24 drops to its original position in which position high frequency apparatus 11 is put in the circuit so instantaneously restar that the device '7 is almost ted. On the starting of the an electric discharge is establever 24 to cut out of ciroperating discharge the high frequency apparatus is again out out of circuit as described above.

During the operation of said device 7 else trodes 5 and 6 are maintained at an electron emitting temperature by the operating current. As transformer 15, 16; 17 is connected into the cir=- cuit only during the short startingperiod it may be considerably underdimensioned with respect to the starting current without harmful efiects thereto. The heating circuit for the electrodes 5 and 6 may be connected to a separate current source, as may the high frequency apparatus, it is essential however that the relay 22, 23 connected into one oi the electrode leads 3 be'adapt ed to operate the switch lever 24 connected into lead 10 or the high frequency apparatus:

While I have shown and described and have pointed out in the anneized claims certain novel features of the invention, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its use and operation may be made by those skilled iii the art without departing from the broad spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

l. In combination, an electric discharge device comprising a container, electrodes sealed therein, one terminal of said electrodes being connected across the terminals of a current source source for said device, a starting circuit for said device comprising both a high frequency apparatus and a circuit connected across me other terminals of said electrcdes tc meager;

2. In combination, an electric discharge de-'* vice comprisinga container, electrodes sealed therein, one of the two terminals of each oi said electrodes being connected across the ter minals of a current source for said device, a starting circuit for said device comprising both a high frequency apparatus and a circuit connected "across the other terminals of said electrodes to causethe heating thereofland a single meansconnected into one of the leads from the terminals of said current source to the electrodes of said device adapted to cut out of circuit both elements of said starting circuit instantly on the start of an operating electric discharge in said electric discharge device.

3. In combination, in electric discharge device comprising a container, thermionic electrodes sealed therein, said electrodes being connected across the terminals of a current source for said device by one terminal of each electrode, a start ing circuit for said device comprising a high frequency apparatus and a circuit connected across the other terminals of said electrodes to cause the heating thereof, and means responsive to current now through the device for cutting out of circuit said starting circuit instantly on thestart of an operating electric discharge in said electric discharge device.

chairman cam. 

